Pregnant NCIS: Los Angeles star Daniela Ruah is dishing about the challenges that come with camouflaging her growing belly while filming.

"This is not easy to hide anymore," Ruah tells ET. "I think the camera angles probably and wardrobe have been the biggest secret."

WATCH: Daniela Ruah and Sarah Wright Olsen Dish on Real-Life 'NCIS: Los Angeles' Baby Triangle

Ruah and husband David Olsen are expecting their second child -- a daughter -- this year, but Ruah will still be in every episode of the CBS drama thanks to the craftiness of the crew.

"There's one scene where she's got a sniper rifle out and she's supposed to be lying on her stomach," says Ruah's co-star and brother-in-law Eric Christian Olsen. "I looked around and I was like, 'How are we doing to do this? She's got a giant baby in her belly,' and everyone kind of stares around like, 'Should we dig a hole?' So we are digging a hole in the desert, so she can lie and place her belly into this hole!"

Meanwhile, her baby bump is front and center on the cover of the latest issue of Fit Pregnancy magazine.

WATCH: 'NCIS: LA' Stars Eric Christian Olsen and Daniela Ruah on Densi

"I feel incredible," Ruah shares.

But Ruah and her husband aren't the only ones excited for their new arrival. The couple's 2-year-old son, River, can't wait to be a big brother. Ruah told us that River kisses her belly "all the time" and talks to his unborn sister.

PICS: Hollywood's Cutest Kids

"He puts on a baby voice and says, 'You want to come out? You want to come out?' and I'm like, 'She'll be here soon!'"

NCIS: Los Angeles returns to CBS on Oct. 2.